Thatcher warned Japan to open its markets.

The British prime minister issued a thinly veiled threat of trade sanctions against Japan unless Tokyo opened its domestic market to foreigners. Margaret Thatcher told Parliament she regarded the application by British electronics firm Cable & Wireless to invest in a proposed new Japanese telecommunications company as a test case of how open the Japanese market really is. British businesses have grown increasingly resentful of Japan’s refusal to open its markets and have called on the government to revoke the licenses of Japanese institutions operating in London.